meningioma

16
7/15/2019 Meningioma http://slidepdf.com/reader/full/meningioma-563383a96128a 1/16 Meningioma Author: Georges Haddad, MD, Clinical Assistant Professor, Department of Medicine, Division of Neurosurgery, American University of Beirut, Lebanon Coauthor(s): Ali Turkmani, MD, Staff Physician, Department of Neurosurgery, American University Hospital; Tarafa Baghdadi, MD, Staff Physician, Department of  Neurosurgery, American University Hospital; Roukoz B Chamoun, MD, Staff Physician, Department of Neurosurgery, American University of Beirut Medical Center Contributor Information and Disclosures Updated: Jun 30, 2009 Print This Email This Overview Differential Diagnoses & Workup Treatment & Medication Follow-up Multimedia References Keywords Further Reading Introduction Background Meningioma, the term coined by Harvey Cushing, refers to a set of tumors that arise contiguously to the meninges. Pathophysiology Meningiomas may occur intracranially or within the spinal canal. They are thought to arise from arachnoidal cap cells, which reside in the arachnoid layer covering the surface of the brain. Meningiomas commonly are found at the surface of the brain, either over the convexity or at the skull base. In rare cases, meningiomas occur in an intraventricular or intraosseous location. The problem of classifying meningioma is that arachnoidal cells may express both mesenchymal and epithelial characteristics. Other mesodermal structures also may give rise to similar tumors (eg, hemangiopericytomas or sarcomas). The classification of all of these tumors together is controversial. The current trend is to

Upload: arief-kurniawan

Post on 30-Oct-2015

24 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 1/16

Meningioma

Author: Georges Haddad, MD, Clinical Assistant Professor, Department of Medicine,Division of Neurosurgery, American University of Beirut, Lebanon

Coauthor(s): Ali Turkmani, MD, Staff Physician, Department of Neurosurgery,American University Hospital; Tarafa Baghdadi, MD, Staff Physician, Department of 

 Neurosurgery, American University Hospital; Roukoz B Chamoun, MD, Staff Physician, Department of Neurosurgery, American University of Beirut Medical Center 

Contributor Information and Disclosures

Updated: Jun 30, 2009

• Print This

• Email This

Overview• Differential Diagnoses & Workup

• Treatment & Medication

• Follow-up

• Multimedia

• References

• Keywords

• Further Reading

Introduction

Background

Meningioma, the term coined by Harvey Cushing, refers to a set of tumors that arisecontiguously to the meninges.

Pathophysiology

Meningiomas may occur intracranially or within the spinal canal. They are thought toarise from arachnoidal cap cells, which reside in the arachnoid layer covering the surface

of the brain.

Meningiomas commonly are found at the surface of the brain, either over the convexity

or at the skull base. In rare cases, meningiomas occur in an intraventricular or intraosseous location. The problem of classifying meningioma is that arachnoidal cells

may express both mesenchymal and epithelial characteristics. Other mesodermal

structures also may give rise to similar tumors (eg, hemangiopericytomas or sarcomas).The classification of all of these tumors together is controversial. The current trend is to

Page 2: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 2/16

separate unequivocal meningiomas from other less well-defined neoplasms.

Undoubtedly, advances in molecular biology will allow scientists to determine the exact

genomic aberration responsible for each specific neoplasm.

Frequency

United States

The annual incidence of symptomatic meningiomas is approximately 2 cases per 100,000

individuals. Meningiomas account for approximately 20% of all primary intracranial

neoplasms. However, the true prevalence is likely higher than this because autopsy

studies reveal that 2.3% of individuals have undiagnosed asymptomatic meningiomas.Meningiomas are multiple in 5-40% of cases, particularly when they associated with

neurofibromatosis type 2 (NF2). Familial meningiomas are rare unless associated with

 NF2.1 

International

The frequency of meningiomas in Africa is nearly 30% of all primary intracranial tumors.

Mortality/Morbidity

Mortality and morbidity rates for meningiomas are difficult to assess. Some meningiomasare discovered fortuitously when CT or MRI is done to assess for unrelated diseases or 

conditions. Therefore, some patients die with meningioma and not from it. Estimates of 

the 5-year survival usually range from 73-94%.

• Meningiomas usually grow slowly, and they may produce severe morbidity before causing death.

• Factors that may be predictive of a high postoperative morbidity rate include

 patient-related factors (eg, advanced age, comorbid states such as diabetes or 

coronary artery disease, preoperative neurological status), tumor factors (eg,location, size, consistency, vascularity, vascular or neural involvement), previous

surgery, or previous radiation therapy.

Race

Meningiomas are more prevalent in Africa than in North America or Europe. In Los

Angeles County, meningioma is reported more commonly in African Americans than inothers.

Sex

Meningiomas afflict women more often than men. The male-to-female ratio ranges from1:1.4 to 1:2.8.

Page 3: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 3/16

• The female preponderance may be less pronounced in the black population than in

other groups.

• Meningiomas are equally distributed between boys and girls.

Age

The incidence increases with age. Ages and corresponding incidence rates reported from2002 are as follows:

• Age 0-19 years - 0.12

• Age 20-34 years - 0.74

• Age 35-44 years - 2.62

• Age 45-54 years - 4.89

• Age 55-64 years - 7.89

• Age 65-74 years - 12.79

• Age 75-84 years - 17.04

• Age 85 years and older - 18.86

Clinical

History

Meningiomas produce their symptoms by several mechanisms. They may causesymptoms by irritating the underlying cortex, compressing the brain or the cranial nerves,

 producing hyperostosis2 and/or invading the overlying soft tissues, or inducing vascular 

injuries to the brain. The signs and symptoms secondary to meningiomas may appear or 

 become exacerbated during pregnancy but usually abate or improve in the postpartum period.

• Irritation: By irritating the underlying cortex, meningiomas can cause seizures.

 New-onset seizures in adults justify neuroimaging (eg, MRI) to exclude the

 possibility of an intracranial neoplasm.

• Compression: Localized or nonspecific headaches are common. Compression of 

the underlying brain can give rise to focal or more generalized cerebral

dysfunction, as evinced by focal weakness, dysphasia, apathy, and/or somnolence.

• Stereotypic symptoms: Meningiomas in specific locations may give rise to the

stereotyped symptoms listed in the Table. These stereotypical symptoms are not

 pathognomonic of meningiomas in these locations; they may occur with other 

conditions or lesions. Conversely, meningiomas in these locations may remainasymptomatic or produce other unlisted symptoms. Table 1. Symptoms and Signs

Associated with Meningiomas in Specific Locations

Open table in new window

[ CLOSE WINDOW ]

Page 4: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 4/16

Table

Location  Symptoms 

Parasagittal Monoparesis of the contralateral leg

Subfrontal Change in mentation, apathy or disinhibited behavior, urinary

incontinenceOlfactory groove Anosmia with possible ipsilateral optic atrophy and

contralateral papilledema (this triad termed Kennedy-Foster syndrome)

Cavernous sinus Multiple cranial nerve deficits (II, III, IV, V, VI), leading to

decreased vision and diplopia with associated facial numbness

Occipital lobe Contralateral hemianopsia

Cerebellopontine

angle

Decreased hearing with possible facial weakness and facial

numbness

Spinal cord Localized spinal pain, Brown-Sequard (hemispinal cord)syndrome

Optic nerve Exophthalmos, monocular loss of vision or blindness,

ipsilateral dilated pupil that does not react to direct light

stimulation but might contract on consensual light stimulation;often, monocular optic nerve swelling with optociliary shunt

vessels

Sphenoid wing Seizures; multiple cranial nerve palsies if the superior orbitalfissure involved

Tentorial May protrude within supratentorial and infratentorial

compartments, producing symptoms by compressing specific

structures within these 2 compartments 3 

Foramen magnum Paraparesis, sphincteric troubles, tongue atrophy associatedwith fasciculation

Location  Symptoms 

Parasagittal Monoparesis of the contralateral leg

Subfrontal Change in mentation, apathy or disinhibited behavior, urinary

incontinence

Olfactory groove Anosmia with possible ipsilateral optic atrophy andcontralateral papilledema (this triad termed Kennedy-Foster 

syndrome)

Cavernous sinus Multiple cranial nerve deficits (II, III, IV, V, VI), leading to

decreased vision and diplopia with associated facial numbness

Occipital lobe Contralateral hemianopsiaCerebellopontine

angle

Decreased hearing with possible facial weakness and facial

numbness

Spinal cord Localized spinal pain, Brown-Sequard (hemispinal cord)

syndrome

Optic nerve Exophthalmos, monocular loss of vision or blindness,

ipsilateral dilated pupil that does not react to direct light

Page 5: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 5/16

stimulation but might contract on consensual light stimulation;

often, monocular optic nerve swelling with optociliary shuntvessels

Sphenoid wing Seizures; multiple cranial nerve palsies if the superior orbital

fissure involved

Tentorial May protrude within supratentorial and infratentorialcompartments, producing symptoms by compressing specific

structures within these 2 compartments 3 

Foramen magnum Paraparesis, sphincteric troubles, tongue atrophy associated

with fasciculation

• Vascular: This presentation, although rare, should be considered. Meningiomas of 

the skull base may narrow and even occlude important cerebral arteries, possibly

 presenting either as transient ischemic attack (TIA)–like episodes or as stroke.

• Miscellaneous

o Intraventricular meningiomas may present with obstructive

hydrocephalus.

o Meningiomas in the vicinity of the sella turcica may produce panhypopituitarism.

o Meningiomas that compress the visual pathways produce various visual

field defects, depending on their location.

o Rarely, chordoid meningiomas can present with hematologic disturbances,

namely Castleman syndrome.4 

Physical

The physical findings mirror the aforementioned symptoms and include signs due to

raised intracranial pressure, involvement of cranial nerves, compression of the underlying

 parenchyma, and involvement of bone and subcutaneous tissues by the meningioma.

• Raised intracranial pressure leads to papilledema, decreased mentation and,

ultimately, to brain herniation.

• Involvement of the cranial nerves may lead to anosmia, visual field defects, optic

atrophy, diplopia, decreased facial sensation, facial paresis, decreased hearing,

deviation of the uvula, and hemiatrophy of the tongue.

• Compression of the underlying parenchyma may give rise to pyramidal signs that

are exemplified by pronator drift, hyperreflexia, positive Hoffman sign, and presence of the Babinski sign. Parietal-lobe syndrome may occur if the parietal

lobes are compressed.

o Compression of the dominant (usually left) parietal lobe may give rise to

Gerstmann syndrome: agraphia, acalculia, right-left disorientation, and

finger agnosia.

o Compression of the nondominant (usually right) parietal lobe leads to

tactile and visual extinction and neglect of the contralateral side.o Compression of the occipital lobes leads to a congruent homonymous

hemianopsia.

Page 6: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 6/16

• Spinal meningiomas may give rise to a Brown-Sequard syndrome (ie,

contralateral decreased pain sensation, ipsilateral weakness, decrease in position

sense), sphincteric weakness and, ultimately, complete quadriparesis or  paraparesis.

Causes

• Trauma and viruses have been investigated as possible causative agents for 

development of meningiomas. However, no definitive proof has yet been found.

• The role of inflammation (eg, posttraumatic insult) resulting in the upregulation of 

COX-2 has been investigated in the tumorogenesis of meningiomas.5 

• On the other hand, the role of radiation in the genesis of meningiomas has been

shown.

o Patients subjected to low-dose irradiation for tinea capitis may develop

multiple meningiomas decades later in the field of irradiation.

o High-dose cranial irradiation may induce meningiomas after a short

latency period.• Genetic causes have been implicated in the development of meningiomas.

o The best-characterized and most common genetic alteration is the loss of 

the NF2 gene ( NF2) on chromosome 22q6 .  NF2 encodes a tumor 

suppressor known as merlin (or schwannomin).

o Of interest, the meningioma locus is close to but probably different from

the gene responsible for NF2.

o Up to 60% of sporadic meningiomas were found to harbor  NF2 mutations.

o Other cytogenetic alterations are chromosomal loss of 1p, 3p, 6q, and 14q.

o Loss of chromosome 10 is associated with increased tumor grade,

shortened time to recurrence, and shortened survival.

o Progression to anaplastic meningioma has been associated withinvolvement of chromosomal site 17q.

o The following events were found to be associated with higher grades of 

meningiomas: loss of the tumor suppressor in lung cancer-1 gene (TSLC-

1), loss of progesterone receptors, increased expression of cyclooxygenase

2 and ornithine decarboxylase.

o Monosomy of chromosome 7 is a rare cytogenetic change. However, it is

frequently reported in radiation-induced meningiomas.

o The invasive potential of meningioma cells seems to be reflected by a

 balance between the expression of matrix metalloproteinases (MMPs) and

tissue inhibitors of MMPs (TIMPs).

o The most consistent chromosomal abnormality isolated in meningiomas ison the long arm of chromosome 22.

o Meningiomas can also be associated with different genetic syndromes,

namely Gorlin7 and Rubinstein-Taybi syndromes8 .

• Several findings suggest an association between hormones and the risk for 

meningiomas, including increased incidence in women versus men and the

 presence of estrogen, progesterone, and androgen receptors on some of these

Page 7: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 7/16

tumors. However, the exact nature of this relationship and its implication on the

management of meningiomas remain under investigation.

• Whether cell phone use increases the risk of meningiomas (and of brain tumors in

general) remains of great interest, especially with the recent tremendous increase

in the use of these devices worldwide. At present, the available data do not

support such an association; however, all published studies have relatively smallsample sizes and a short period of follow-up.9 

eMedicine Specialties > Neurology > Neuro-oncology

Meningioma: Differential Diagnoses &

Workup

Author: Georges Haddad, MD, Clinical Assistant Professor, Department of Medicine,

Division of Neurosurgery, American University of Beirut, LebanonCoauthor(s): Ali Turkmani, MD, Staff Physician, Department of Neurosurgery,

American University Hospital; Tarafa Baghdadi, MD, Staff Physician, Department of 

 Neurosurgery, American University Hospital; Roukoz B Chamoun, MD, Staff Physician, Department of Neurosurgery, American University of Beirut Medical Center 

Contributor Information and Disclosures

Updated: Jun 30, 2009

• Print This

• Email This• Overview

• Differential Diagnoses & Workup

• Treatment & Medication

• Follow-up

• Multimedia

• References

• Keywords

• Further Reading

Differential Diagnoses

Brainstem Gliomas  Neurofibromatosis, Type 1

Cavernous Sinus Syndromes Neurofibromatosis, Type 2

Complex Partial Seizures Oligodendroglioma

Craniopharyngioma Persistent Idiopathic Facial PainFrontal Lobe Syndromes Pituitary Tumors

Page 8: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 8/16

Glioblastoma Multiforme Primary CNS Lymphoma

Low-Grade Astrocytoma

Other Problems to Be Considered

Back pain

Workup

Laboratory Studies

 No specific laboratory tests are used to screen for meningioma.

Imaging Studies

Imaging studies are the mainstay of diagnosis (see Media files 1-7).

Case 1: Surgical view of the tumor. The dura is opened, and the meningioma

can be seen extending en plaque over the surface of the brain.

[ CLOSE WINDOW ]

Page 9: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 9/16

Case 1: Surgical view of the tumor. The dura is opened, and the meningioma

can be seen extending en plaque over the surface of the brain.

• Plain skull radiograph may reveal hyperostosis and increased vascular markings

of the skull, as well as intracranial calcifications.

• On plain head CT scans, meningiomas are usually dural-based tumors that are

isoattenuating to slightly hyperattenuating.

o They enhance homogeneously and intensely after the injection of 

iodinated contrast material.

o Perilesional edema may be extensive. Hyperostosis and intratumoral

calcifications may be present.

o The tumor compresses the brain without invading it.

o Multiple meningiomas may be difficult to differentiate from metastasis.

• On T1- and T2-weighted MRIs, the tumors have variable signal intensity. If a

meningioma is suspected, obtaining an enhanced MRI is imperative.

o

Meningiomas enhance intensely and homogeneously after injection of gadolinium gadopentetate.

o The edema may be more apparent on MRI than on CT scanning.

o An enhancing tail involving the dura may be apparent on MRI.

o Cystic meningiomas may exhibit intratumoral or peritumoral cysts. The

 peritumoral cysts may actually represent a gliotic response and may not

necessitate surgical extirpation.

Page 10: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 10/16

• Endovascular angiography allows the surgeon to preoperatively determine the

vascularization of the tumor and its encroachment on vital vascular structures.

o Late venous images are important to determine the patency of the involved

dural sinuses.

o Angiographic features of meningiomas include the following:

Supply from the external circulation Mother-in-law blush (which comes early and leaves late)

Sunburst or radial appearance of the feeding arteries

o Although magnetic resonance arteriography (MRA) and magnetic

resonance venography (MRV) have decreased the role of classical

angiography, the latter remains a powerful tool for planning surgery.

o Angiography is still indispensable if embolization of the tumor is deemed

necessary.

•  New research tools such as positron emission tomography (PET), including

octreotide-PET, or magnetic resonance spectroscopy (MRS) have been used to

 predict in vivo the aggressiveness of meningiomas.10 

Procedures

• Preoperative endovascular embolization of the vascular feeders from the external

circulation may be beneficial in extremely vascular meningiomas.11 

• If this is the case, resection should be performed shortly after embolization to

decrease the likelihood of tumor revascularization.

Histologic Findings

Meningiomas are usually globular, well-demarcated neoplasms. They have a wide dural

attachment and become invaginated into the underlying brain without invading it. Their cut surface is either translucent pale or homogeneously reddish brown. It may be gritty on

cutting. Some meningiomas occur as a sheetlike extension that covers the dura but does

not invaginate the parenchyma; this variant is called meningioma en plaque. The last

morphologic variant is the cavernous sinus meningioma that infiltrates the cavernoussinus and becomes interdigitated with its contents. The 3 most common histologic

subtypes of meningiomas are the meningothelial (syncytial), transitional, and fibroblastic

meningiomas. See Media files 8-9 for representative pathologic views of varioussubtypes.

Page 11: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 11/16

Case 2: Bone flap was removed. Note tumoral breach of the dura. The dura and

overlying skull were removed surgically. Duraplasty and cranioplasty were

performed

[ CLOSE WINDOW ]

Page 12: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 12/16

Case 2: Bone flap was removed. Note tumoral breach of the dura. The dura andoverlying skull were removed surgically. Duraplasty and cranioplasty were

performed

Page 13: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 13/16

Case 2: Surgical specimen. Complete resection was achieved.

[ CLOSE WINDOW ]

Page 14: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 14/16

Page 15: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 15/16

Case 2: Surgical specimen. Complete resection was achieved.

Meningothelial meningiomas reveal densely packed cells that are arranged in sheets with

no clearly discernible cytoplasmic borders. Although not prominent, whorls are present(calcified whorls are termed psammoma bodies). Nuclei show intranuclear vacuoles.

Fibroblastic (fibrous) meningiomas reveal sheets of interlacing spindle cells. Theintercellular stroma is composed of reticulin and collagen. The transitional variety reveals

features common to both the meningothelial and fibroblastic varieties; others include

angiomatous, microcystic, secretory, clear cell, choroid, lymphoplasmacyte-rich, papillary, and metaplastic variants.

Meningiomas may be associated with hyperostosis.2 The exact nature of the cause of this

hyperostosis is controversial (ie, reactive versus tumoral infiltration).

Immunohistochemistry

Immunohistochemistry can help diagnose meningiomas, which are positive for epithelialmembrane antigen (EMA) in 80% of cases. They stain negative for anti-Leu 7 antibodies

(positive in schwannomas) and for glial fibrillary acidic protein (GFAP). Progesterone

receptors can be demonstrated in the cytosol of meningiomas; the presence of other sex

hormone receptors is much less consistent. Somatostatin receptors also have beendemonstrated consistently in meningiomas.

Malignancy

The notion of malignancy in meningiomas is still vague.12 Some histologic variants, such

as papillary meningioma, undoubtedly carry a less favorable prognosis than other histologic types. Two features are considered clear signs of malignancy: cortical invasion

 by the tumor and distal metastasis. Of note, in the 2007 WHO grading scheme, brain

invasion is considered a criterion for atypia.

Several stains have been used to help predict the behavior of meningiomas. These stainsquantify the mitotic rate of these tumors. Bromodeoxyuridine (BudR) labeling requires an

intravenous (IV) injection before tumor removal. On the other hand, immunohistologic

staining for proliferating cell nuclear antigen (PCNA) can be performed on fixed

specimens. Some have attempted to correlate the pathology and behavior of meningiomasto the loss of specific genetic material.

The World Health Organization classification of meningiomas is presented in Table 2.

Table 2. Summary of the 2007 WHO Grading Scheme for Meningiomas

Open table in new window

Page 16: Meningioma

7/15/2019 Meningioma

http://slidepdf.com/reader/full/meningioma-563383a96128a 16/16

[ CLOSE WINDOW ]

Table

WHO

Grade  Histological Subtype  Histological Features I Meningothelial, fibroblastic,

transitional, angiomatous,

microcystic, secretory,lymphoplasmacytic metaplastic,

 psammomatous

Does not fulfill criteria for grade II or III

II (Atypical) Chordoid, clear cell 4 or more mitotic cells per 10 hpf and/or  

3 or more of the following: increasedcellularity, small cells, necrosis,

 prominent nucleoli, sheeting, and/or 

 brain invasion in an otherwise Grade I

tumor III

(Anaplastic)

Papillary, rhabdoid 13  20 or more mitoses per 10 hpf and/or 

obviously malignant cytologicalcharacteristics such that tumor cell

resembles carcinoma, sarcoma, or 

melanoma

WHO

Grade  Histological Subtype  Histological Features 

I Meningothelial, fibroblastic,

transitional, angiomatous,microcystic, secretory,

lymphoplasmacytic metaplastic, psammomatous

Does not fulfill criteria for grade II or III

II (Atypical) Chordoid, clear cell 4 or more mitotic cells per 10 hpf and/or  3 or more of the following: increased

cellularity, small cells, necrosis,

 prominent nucleoli, sheeting, and/or  brain invasion in an otherwise Grade I

tumor 

III

(Anaplastic)

Papillary, rhabdoid 13  20 or more mitoses per 10 hpf and/or 

obviously malignant cytologicalcharacteristics such that tumor cell

resembles carcinoma, sarcoma, or melanoma